UNI-T LM520 LM530 LM550 Touch Red Laser Level Instrument 2/3/5 Line Cross Marking Instrument    Features:     I. Introduction     These series products adopt diode laser beam, the waveform length of which is 532nm. The level laser can generate two or more laser sectors and one plump down point. The sector is formed by one horizontal beam and one or more vertical beams that is reflected on the wall. The included angle of every two vertical beams is 90& 730;. The focus of those beams is called Zenith.     Automatic self-leveling     Indoor and outdoor(long distance) mode     360& 730; rotatable ; Adjustable structure for accurate targeting     Water-proof, dirt-proof, sensitive buttons           II. Structure     Vertical beam button     Horizontal beam button     Bubble vials     Outdoor mode button     Vertical laser emission window     Horizontal laser emission window     Power switch/lock     Thumbscrew     Adjustable bracket           III. Operation instructions     1. Place the device on a tripod or a flat surface. Ensure the device is approximately on horizontal level     Note: If the device is out of level, the laser will be shut down automatically with audio alert.     2. Rotate the power switch clockwise to turn on the device. Laser beams are emitted with the green LED ON.     3. Rotate the device to make the laser beam pointing at the target.     4. Turn the thumb screw to locate the exact position.     5. After every task, turn the power switch anticlockwise to turn off the device.           Maintenance     1. Never let any liquid get inside the device. Never immerse any part of the device into a liquid.     2. Avoid shock and drop during operation and storage.     3. Please turn off the device before moving the device or it may affect the accuracy.     4. Keep the laser emission window clean. Use soft cloth to wipe the glass lens if there is dirt.     5. Take off the battery and store the device in the kit box if the device is not in use for long time.